I received a zero-degree down sleeping bag over the holidays and I'm eager to do some winter camping in Colorado later this month. I've been on plenty of warm-weather trips, but this will be my first winter camp. What else do I need to stay warm?
A good sleeping bag is essential on winter trips, but often it isn’t enough. Here are a couple easy things you can do to stay warm.
First, consider carrying an extra sleeping pad. When you lie on your bag, you compress its insulation and most cold will come from beneath you. If you already have a decent self-inflating pad, I recommend bringing a Therm-a-Rest Z-Lite full-length pad ($40). It adds very little weight to your kit—only 14 ounces—but offers a substantial amount of extra insulation when you lie down.
Second, pack a full set of long underwear. There’s an old myth that you’ll be warmer when you're almost naked, but don't believe it—insulation is insulation. I like Icebreaker's Bodyfit 200-weight series for an all-purpose winter base layer—the men’s Oasis Crewe top is $80 and worth every penny. Also pack some dry socks, and a warm cap like Smartwool's Lid ($35).
At bedtime, have a long drink of water and eat an energy bar or something calorie rich. The water and food will help you generate a bit of extra heat. And when it's really cold, I usually fill a water bottle with warm water. Secure the lid tightly and stick it down by your feet. You'll warm up quickly and sleep comfortably.